<!DOCTYPE html>
<html lang="en">
<head>
    <meta charset="UTF-8">
    <meta name="viewport" content="width=device-width, initial-scale=1.0">
    <title>Document</title>
    <script src="https://cdn.jsdelivr.net/npm/vue/dist/vue.js"></script>

</head>
<body>
    <div id="app">
        <button @click="test($event,12)">{{msg}}</button>
        <div>{{time}}</div>
    </div>
    <script>
        new Vue({
            el:'#app',
            data:{
                msg:'hello',
                time:new Date().toLocaleString(),
            },
            methods:{
                test(e,num){
                    // alert(1);
                    console.log(e,num);
                    this.msg = '123';
                    this.time = new Date().toLocaleString();
                }
            },
        })
    </script>

</body>
</html>